Apparatus for projecting images of transparent or opaque objects and script on a screen



May 19, 1942.

APPARATUS FOR PROJECTING IMAGES OF TRANSPARENT OR OPAQU J M. KREININ AND SCRIPT ON A SCREEN Filed May 22. 195.9

E OBJECTS Patented May 19, 1942 APPARATUS FOR PROJECTING IMAGES OF TRANSPARENT R OPAQUE OBJECTS AND SCRIPT ON A SCBEEN Jacob Marcovich Kreinin, Moscow, Union of Soviet Socialist Republics Application May 22, 1939, Serial No. 275,084. In

the Union oi Soviet Socialist Republics February 3, 1939 6 Claims.

Apparatuses are known for projecting images of transparent or opaque objects, microscopic slides, script on a screen. These apparatuses rays of light onto the opaque object for projection by reflected light. or through a transparency for direct projection.

In the drawing, Fig. 1 shows the first mentioned form of the proposed apparatus, Fig. 2 shows an accessory for projecting ordinary and cinematographic films and Fig. 3 shows another accessory for projecting microscope slides.

The apparatus shown in Fig. 1 of the drawing comprises a casing I in which there is a movable mirror 2 fastened to a special support. The mirror 2 when in position shown in full lines serves to direct the rays of light from the lamp assembly l6-2l through condenser 9 and lens l4 onto mirror 3 which reflects them onto the screen. When the mirror 2 is in the position marked 2 it serves to direct the rays of light onto an opaque object placed on object table I so that the light reflected from it is projected by lens l2 and mirror 6 onto the screen. Mirror 3 is attached to mirror 6 by a hinge andwhen the apparatus is not being used, mirror 3 is lowered to position 3 when it closes the apparatus.

The housing of lens I4 is pivoted so that when mirror 3 is lowered.to position 3 it can be turned aside. A lever i3 is supplied for pressing the object table 1 against the frame opening l0.

Lens I may be furnished with a reflecting prism to take'place of mirror 3.

The lamp assembly installed inside the body of the apparatus consists of a filament ,or highpressure vapour electric lamp H, a reflector mirror IS, a heat absorbing filter l9 and a condenser l8. The whole assembly can be turned about a pivot so as to directly illuminate an opaque object placed on table 1. An electric fan II is mounted in the base of the box by means of a casing 4 having hole for admitting cooling air,

while at thetop of the box there are slots l5 for the heated air to escape through. The ventilator fan can also be installed in the top of the lantern casing with the slots for admitting cold air at the bottom.

For projecting ordinary and cinematographical films an accessory illustrated in Fig. 2 is supplied. It consists of a bracket 22 a prismv 23 with a silvered reflecting hypotenuse replacing mirror 3, a lens 24 of short focal length, drums 25 for holding the flhn, a frame 26 and condenser lens not shown in the drawing.

Apart from this accessory there is another illustrated in Fig. 3 for projecting microscope slides. It consists of a bracket", prism 29, spe-- cial lens 30, frame window 3| and press-springs 33 with nuts 32 for holding the slide.

The'proposed apparatus is used in the following manner. For projecting drawings, plans, books, drawings, etc., by reflected light, the objects to be projected on the screen are placed on object table I and by means of lever l3 are pressed against the frame opening l0. Mirror 2 is turned to the position 2 shown in dotted lines in the drawing. When projecting three-dimensioned models, globes etc., table I can be lowered quite suiflciently, but if necessary, it can be turned away so as not to interfere with the object being projected. The adjustment of the table is effected by a rotatable eccentric 40 engaging in a slot 4| in the lever I3 adjacent the pivotal support 42 therefor.

The lamp assembly is not moved, the rays of light being reflected from mirror 2 in the posi-- tion 2 onto the object and then by means of lens l2 and mirror 6 are projected onto a screen.

Lens I4 is moved aside so as not to obscure the The beam of light passes through condenser 9 and lens l4 and after reflection at mirror 31s projected onto a screen. f

For projecting writing, etc., a ground glass or a transparent Cellophane strip on which the writing is made byv a special pencil, is placed in the frame 8 situated above condenser 9, while the lamp assembly and mirror 2 are in the position used for projecting transparencies.

For projecting ordinary or cinematographic films the accessory according to Fig. 2 is placed on frame- 8.while lens I4 is moved to one-side, and finally for projecting microscope slides, the

accessory accoring to Fig. 3 or an ordinary microscope and condenser is placed on frame 8.

For convenience in operation the apparatus may be furnished with means not shown in the drawing for controlling the light source, for tuming the mirror and lenses, these means being operated from the switch board.

I claim:

1. An apparatus for projecting images of transparencies, opaque objects, pictures and the like on a screen comprising two lenses'arranged side by side, mirror means angularly related to said lenses for reflecting images projected by said lenses onto a screen, a single lighting unit con-' 'sisting of a lamp and a condenser, a second condenser arranged in front of one of said lenses, a

said lenses onto a screen, a single lighting unit, a

holder for transparencies in'i'ront of one of said lenses, 9. table for supporting objects and pictures arranged beneath the other lens, and an adjustable reflector fordirecting the light from said lighting unit either upon, the table or said holder.

3. An apparatus as claimed in claim 2, char.- acterized in that said lighting unit includes a reflector, heat absorbing filter and condenser.

4. A device for use in connection with the apparatus claimed in claim 1, comprising a microscopic lens and a. prism arranged adjacent said lens and means for holding microscopic slides adjacent the microscopic lens.

5. A device for use in conjunction with the apparatus defined in claim 1, comprising lens of short focal length, a reflector prism arranged adjacent said lens and means for supporting motion picture film adjacent said lens.

6. An apparatus as claimed in claim 1 characterized by the provision of a casing enclosing the lighting unit and the second reflector and means for cooling said chamber.

JACOB MARCOVICH KREININ. 

